A free AI detector with no sign-up

IsThisAiWritten is a free AI detector with no sign-up at all. Nobody asks for an email address, there's no trial clock, and every part of the report is included, so you can ask “is this AI?” about a paragraph without handing over anything about yourself. Paste the text you're wondering about below and press Check for AI.

What “free” usually means for AI detectors

Lots of detectors call themselves free. The small print usually adds a meter of some kind. At the time of writing:

• Pangram's free plan gives 20 credits a day, which it says is enough to scan up to 2,000 words.
• GPTZero checks up to 10,000 characters without an account and asks you to create a free account for anything longer.
• Originality.ai allows three free scans a day without an account, each up to 2,000 words.
• Winston AI's free plan is a 14-day trial with 2,000 credits, started from a registration page.

None of that is unreasonable. Those companies run their models on their own servers and pay for each check, so a meter or a paid plan can be a fair trade. It just helps to know what you are signing up for.

Why this detector can be free without an account

The detection runs inside your browser. On your first full check, the browser downloads an open classifier called TMR (based on RoBERTa, 131 MB) from Hugging Face and caches it. From then on, each check happens on your own machine. We don't pay per check, so there are no credits to sell and no reason to put anything behind a login. And since there's no account, there's no history of your checks sitting on a server either.

What you get from a free AI detector with no sign-up

You get the whole report, with nothing blurred and no upgrade button. It opens with an outcome (Human, Mixed, AI or Inconclusive) and a confidence word. Next to it sits the AI-likeness line, which tells you how the text compares with human writing we tested. A sentence map shades each sentence relative to the rest of your text. Style signals point out stock phrasing and paired words as context, without feeding the verdict. An invisible-character cleaner flags zero-width spaces and look-alike letters. Fiction also gets a narrative fingerprint. There is no word or character limit, so the same report works for a 200-word email or a full manuscript.

How to run a check without an account

1. Paste at least 50 words of English text into the box above. From 150 words up the result is firmer.
2. Press Check for AI. The first time, give the model a moment to download.
3. Read the outcome and the reason shown with it.
4. Close the tab when you're done. Your text was never saved, so there is nothing to delete.

Can you trust a free detector?

Judge any detector by how it has been tested rather than by its price. Our benchmark is open, so anyone can read how we test it. That testing is also why the site changed: the first version scored hand-picked style rules, and we replaced it with the trained model that runs today.

A free check here is a useful first look, not a final word. Like any detector, it can be wrong in both directions, so treat a result as a reason to look closer, not as proof. If a result could affect someone's grade or job, it should never be the only evidence. Our post on whether AI detectors are accurate goes into the wider picture.

Sources

1. Pangram: What do I get with a free account?, checked October 2026
2. GPTZero AI detector, checked October 2026
3. Originality.ai AI checker, checked October 2026
4. Winston AI pricing, checked October 2026